... 4*AA battery. Digital DynamometerFeatures & Specifications:1.Strong and light dynamometer to weigh the force of gravity or the pulling force2 ... dynamometers with larger capacity4.In weighing the pulling force, the dynamometer has the functions of peak value hold, overload alarm ... weight indication.5.In weighing the force of gravity, the dynamometer support kg/lb conversion and tare, zero functions6.6 ...